From 5b88cc6e3f653b63966fd79b1942a82273912677 Mon Sep 17 00:00:00 2001
From: Andrew Duthie <andrew@andrewduthie.com>
Date: Wed, 3 May 2017 10:18:23 -0400
Subject: [PATCH] Pick only matchers which have internal flag applied

---
 blocks/api/parser.js      | 21 +++++++++++++++------
 blocks/api/query.js       | 31 ++++++++++++++++++++++++++++---
 blocks/api/test/parser.js |  5 +++--
 blocks/api/test/query.js  | 13 ++++++++++---
 4 files changed, 56 insertions(+), 14 deletions(-)

diff --git a/blocks/api/parser.js b/blocks/api/parser.js
index fa1a1ad201e49..09ec75a80050e 100644
--- a/blocks/api/parser.js
+++ b/blocks/api/parser.js
@@ -1,8 +1,8 @@
 /**
  * External dependencies
  */
-import * as query from 'hpq';
-import { escape, unescape } from 'lodash';
+import { parse as hpqParse } from 'hpq';
+import { escape, unescape, pickBy } from 'lodash';
 
 /**
  * Internal dependencies
@@ -19,10 +19,19 @@ import { createBlock } from './factory';
  * @return {Object}               Block attributes
  */
 export function parseBlockAttributes( rawContent, blockSettings ) {
-	if ( 'function' === typeof blockSettings.attributes ) {
-		return blockSettings.attributes( rawContent );
-	} else if ( blockSettings.attributes ) {
-		return query.parse( rawContent, blockSettings.attributes );
+	const { attributes } = blockSettings;
+	if ( 'function' === typeof attributes ) {
+		return attributes( rawContent );
+	} else if ( attributes ) {
+		// Matchers are implemented as functions that receive a DOM node from
+		// which to select data. Use of the DOM is incidental and we shouldn't
+		// guarantee a contract that this be provided, else block implementers
+		// may feel compelled to use the node. Instead, matchers are intended
+		// as a generic interface to query data from any tree shape. Here we
+		// pick only matchers which include an internal flag.
+		const knownMatchers = pickBy( attributes, '_wpBlocksKnownMatcher' );
+
+		return hpqParse( rawContent, knownMatchers );
 	}
 
 	return {};
diff --git a/blocks/api/query.js b/blocks/api/query.js
index 559a9b67069b5..f9e7782660de9 100644
--- a/blocks/api/query.js
+++ b/blocks/api/query.js
@@ -2,10 +2,35 @@
  * External dependencies
  */
 import { nodeListToReact } from 'dom-react';
+import { flow } from 'lodash';
+import {
+	attr as originalAttr,
+	prop as originalProp,
+	html as originalHtml,
+	text as originalText,
+	query as originalQuery
+} from 'hpq';
 
-export * from 'hpq';
+/**
+ * Given a matcher function creator, returns a new function which applies an
+ * internal flag to the created matcher.
+ *
+ * @param  {Function} fn Original matcher function creator
+ * @return {Function}    Modified matcher function creator
+ */
+function withKnownMatcherFlag( fn ) {
+	return flow( fn, ( matcher ) => {
+		matcher._wpBlocksKnownMatcher = true;
+		return matcher;
+	} );
+}
 
-export function children( selector ) {
+export const attr = withKnownMatcherFlag( originalAttr );
+export const prop = withKnownMatcherFlag( originalProp );
+export const html = withKnownMatcherFlag( originalHtml );
+export const text = withKnownMatcherFlag( originalText );
+export const query = withKnownMatcherFlag( originalQuery );
+export const children = withKnownMatcherFlag( ( selector ) => {
 	return ( node ) => {
 		let match = node;
 
@@ -19,4 +44,4 @@ export function children( selector ) {
 
 		return [];
 	};
-}
+} );
diff --git a/blocks/api/test/parser.js b/blocks/api/test/parser.js
index 99671d43cbf15..51c15bd6f92ec 100644
--- a/blocks/api/test/parser.js
+++ b/blocks/api/test/parser.js
@@ -2,11 +2,11 @@
  * External dependencies
  */
 import { expect } from 'chai';
-import { text } from 'hpq';
 
 /**
  * Internal dependencies
  */
+import { text } from '../query';
 import {
 	getBlockAttributes,
 	parseBlockAttributes,
@@ -47,7 +47,8 @@ describe( 'block parser', () => {
 		it( 'should use the query object implementation', () => {
 			const blockSettings = {
 				attributes: {
-					emphasis: text( 'strong' )
+					emphasis: text( 'strong' ),
+					ignoredDomMatcher: ( node ) => node.innerHTML
 				}
 			};
 
diff --git a/blocks/api/test/query.js b/blocks/api/test/query.js
index 4f1fa45472af6..e372cf1df6630 100644
--- a/blocks/api/test/query.js
+++ b/blocks/api/test/query.js
@@ -2,16 +2,23 @@
  * External dependencies
  */
 import { expect } from 'chai';
+import { parse } from 'hpq';
 
 /**
  * Internal dependencies
  */
-import { parse, children } from '../query';
+import * as query from '../query';
 
 describe( 'query', () => {
+	it( 'should generate matchers which apply internal flag', () => {
+		for ( const matcherFn in query ) {
+			expect( query[ matcherFn ]()._wpBlocksKnownMatcher ).to.be.true();
+		}
+	} );
+
 	describe( 'children()', () => {
 		it( 'should return a matcher function', () => {
-			const matcher = children();
+			const matcher = query.children();
 
 			expect( matcher ).to.be.a( 'function' );
 		} );
@@ -20,7 +27,7 @@ describe( 'query', () => {
 			// Assumption here is that we can cleanly convert back and forth
 			// between a string and WPElement representation
 			const html = '<blockquote><p>A delicious sundae dessert</p></blockquote>';
-			const match = parse( html, children() );
+			const match = parse( html, query.children() );
 
 			expect( wp.element.renderToString( match ) ).to.equal( html );
 		} );